Control valve for vacuum operated brakes



July 1940. F. E, H G 2,208,553

' CONTROL VALVE FOR VACUUM OPERATED BRAKES Original Filed March 30, 1936 2 Sheets-Sheet l fly; TTOENEK July 16, 1940.

F. E. HUSSONG CONTROL VALVE FOR VACUUM OPERATED BRAKES 2 Sheets-Sheet 2 Original Filed March 30, 1936 0 0m m m w N N B we f w r w y A 10. m 9 w M Q y //Vx///A aim w l w W wa. www R Q m 4 2 M 5 Jww Patented July 16, 1940 UNETED. STATES CONTROL VALVE. FOR. VACUUM OPERATED- BRAKES Floyd E. Hussong, Los Angcles, Calif.

Substitute for abandoned application Serial No.

71,641, March 30,

1936. This application January 20, 1938, Serial No.'185,9'79

8 Claims. (Cl. 303-54) This invention relates to hand operatedcontrol valves for vacuum operated brakes, particularly to control valves for vacuum responsive apparatus, wherein the suction created in the intake manifold of an internal combustion engine is utilized to cause operation of brakes or other equipment of a vehicle such as a passenger car, truck, or trailer.

An object of this invention is to provide a control valve of this character which is so arranged that its control handle may be moved in either direction to cause operation of the brake apparatus thereby eliminating any possibility of confusion to the driver and also providing one device whereby an operator that may be either left or right handed may conveniently operate the same.

Another object is to provide a control valve of this character which may be readily and quickly adjusted to insure the most desirable brake action under all conditions; and to compensate for weight of any load being carried or to maintain the most satisfactory brake action for wet, icy or dry roads.

Another object is to provide a control valve of this character which incorporates a main valve and a relief valve arrangement wherein the relief valve is held open by the main valve when the main valve is in its sealing position and in which the relief valve is automatically closed upon opening of the main valve, thus insuring equalized pressure in the booster units until it is desired to actuate the brakes, even though the mainvalve should leak.

Another object is to provide a valve structure for vacuum brake apparatus which is particularly simple of construction and of operation, and which may be readily serviced without being disconnected, the valve elements being arranged to facilitate removal and replacement.

A further object is to provide a control valve of this character, which though easily adjusted and serviced, is so arranged as to minimize unauthorized tampering.

4 The invention resides in the parts and combination of parts hereinafter more particularly described and pointed out in the appended claims.

This application is a substitute for my prior application Serial No. 71,641, filed Mar. 30, 1936.

Other objects, advantages and features of invention may appear from the accompanying drawings, the subjoined detail description and the appended claims.

The accompanying drawings illustrate the invention in the form I at present deem preferable.

Figure 1 is: a plan view of my control valve with the operating handle shown fragmentarily and a portion of the cap forming the operating w end of the handle broken away and in section.

Fig. 2 isa front elevational view of my control valve.

Fig. 3 is a sectional view of my control valve taken on line 3-3, Figs. 1 and 6, showing the parts in the position assumed when the control valve is in its neutral position, the main valve being closed and the air relief valve being open.

Fig, 4 is a fragmentary transverse sectional View looking down on the main valve diaphragm and taken on line 4-4, Fig. 3.

Fig. 5 is another fragmentary transverse sectional view taken on line 5-5, Fig. 3, and looking down upon the air relief valve.

Fig. 6 is a substantially diagrammatical View showing my control valve in association with a vacuum brake apparatus, in which are shown a portion of the intake manifold, a booster unit, and the equalizer bar together with the brake rods which extend therefrom.

The vacuum brake apparatus with which my control valve is associated comprises one or more booster units l each of which is provided with diaphragm 2 connected mechanically through a rod' 3 to the equalizer bar 4 or other suitable member of the braking system of the vehicle. The other side of the diaphragm 2 forms a wall of a chamber which is connected by a pipe 5 to my control valve A, which in turn is connected through a pipe 6 to the intake manifold ?*of an internal combustion engine or to a sub-atmospheric pressure tank, not shown.

The pipes 5 and B fit into a housing H of my control Valve, the housing being provided with alined, internally threaded openings l2 and I3 respectively. The opening [2 intersects the side wall of an air chamber M which is open at its upper end to form a valve port provided with a valve seat l5 therearound. The other opening it intersects a vacuum chamber [6 defined in part by the wall of the cylinder l4 and whichis likewise open at its upper end.

The upper end of the housing II is enlarged to form a diaphragm, seat I! which embraces the valve port and chamber IS. A shell I8, having a complementary seat l9 fits over the housing H. Between the seats I! and I9 is clamped the margin of a flexible diaphragm 2!], preferably formed of rubber, or analogous material preferably designed to withstand oil and the like.

The shell 18 is in centered relation over the diaphragm 20 and incorporates a sleeve 2| which extends both upwardly from the shell and downwardly toward but clear of the diaphragm. The sleeve 2| receives a valve lifting member 22 comprising a hollow stem portion 23 guided in the sleeve and having a polygonal shaped bore. The ends of the stem portion are closed, the upper end by a disk 24 through which extends a shaft 25. The lower or inner end of the shaft 25 is threaded to receive a nut 26 which is held from turning by the polygonal shaped bore in which it slideably fits. A spring 21 is interposed between the disk 24 and nut 26, so that upward movement of the shaft 25 acts through the spring 21 to raise the valve lifting member 22.

2B which is slightly upturned at its margin and which engages the diaphragm 20, when raised, to lift the same off from its seat l5. The diaphragm normally rests upon valve seat IE to separate the vacuum chamber Hi from the air chamber l4and thereby seal communication between pipes 5 and B.

Thediaphragm 20, is yieldingly held in its sealing position by a spring 29 mounted between the diaphragm and upper end of the shell I8 and surrounding the sleeve 2|. The spring 29 is relatively large and an equalizing plate 30 slightly dished at its periphery is interposed be tween the spring and diaphragm.

-A spring 29' operating between the upper end of shell l8 and flange'28 normally urges the valve lifting member 22 downwardly so that the flange 28 is normally spaced from the diaphragm 2|].

The upper end of the shaft 25 is provided with a head 3| slotted toreceive a screw driver and adapted to retain a collar 32 on the shaft. The collar is provided with a pair of diametrically disposed arms 33, one of which is shown by dotted lines in Fig. 3 and in elevation in Fig. 1. The arms 33 extend through slots 34 provided in the upper end of the sleeve 2| and engage a cam ring 35 which journals around the protruding upper end of the sleeve 2|. The cam ring is provided with two diametrically disposed low and high points on its upper surface upon which the arms 33 ride, so that, with the arms initially engaging the low points of the cam ring, movement of the cam ring in either direction will raise the collar 32-and consequently the shaft 25. The shaft in turn, operating through the spring 21, causes the flange 28 to raise the diaphragm 2|] off from seat |5. .Stops 36 are provided at the high points of the cam ring. I 7

Fitted over the cam ring 35 and secured thereto by set screws 31- is acap-member 38 from'which extends a lateral handle 35. The cap member 38 is apertured above the shaft 25 and receives a plug screw 40 which, when removed permits access to the head of the shaft 25 for adjusting the tension of spring -21.

For the purpose of determining the pressures in the pipe lines 5 and 6, gauges 42 and 43 are connected with the air chamber l4 and vacuum chamber l6 by ports 44 and 45 respectively.

The lower end of the air chamber 4 is provided with a port a smaller than the port defined by the valve seat |5 and is provided with a down turned marginal lip forming a valve seat 46. Above the valve seat 46 the air chamber I4 is provided with an integral spider 41 having a centered guide sleeve 48. A stem 49 is slidably mounted in the sleeve 48, its upper end is provided with a head 5|]. Between the head 50 and sleeve is interposed a spring 5|. The lower end of stem 49 is threaded to receive a disk shaped valve member 52 that is secured in position on stem 49 by a lock nut 53. The periphery of the valve member 52 is provided with an annular, valve face ring preferably formed of flexible materials The member 52 a nd valve seat 46 form a relief valve to permit atmospheric pressures to be maintained on opposite sides of the diaphragm 2 in the booster unit I.

The lower end of the air chamber I4 is en- ;*closed by a cup-shaped guard shell 55 having The diaphragm 2D is apertured to receive the lower end of the member 22, and below the dia phragm, that is, within the air chamber M, thevalve lifting member is provided with a flange apertures 56 therein. The valve member 52 controls communication between the atmosphere and the pipe 5 leading to the booster unit I.

The spring 5| tends to normally urge the valve member 52 into closed position; however, when the valve lifting member 22 is in its normal or lower position, it engages the head 50 at the upper end of the stem 49, and holds the valve member 52 in open position as shown in Fig. 3. In this connection, it should be noted that the spring. 5| is sufficiently weak to yield to the weight of the valve lifting member 22 and the tension of the spring 29 exerted thereagainst.

To facilitate centering of the arms in the low points of the cam ring 35 radial notches 51 may be provided at such low points. Thus, the initial movement of the valve lifting member may be relatively rapid..

Operation of my hand control valve is as her of the booster unit is exposed to the atmospheric pressure, whereby an equalized pressure against opposite sides of the diaphragm of the booster unit is insured.

Upon turning the handle 39 in either direction, the diaphragm lifting member 22 is raised, first releasing the valve member 52 so as to close communication between the pipe line 5 and the atmosphere. Continued movement of the handle causes the lifting member 22 to raise the diaphragm 20 off of the valve seat l5 causing air to be exhausted from the pipe line 5 and creating a pressure difference in the booster unit which causes its diaphragm 2 to act upon the braking system of the vehicle through the rod 3 -Adjustment of the spring 21 regulates the amount of pressure differential in the booster unit and consequently the tension on the brake apparatus. Thus, by increasing the tension of spring 21 agreater pressure differential occurs between the pipe line 6 and pipe line 5 before diaphragm 20 is forced onto the seat l5 against the action of the spring 21 and the spring 29.

I claim:

l. A control valve for vacuum brakes, comprising a housing structure having a chamber communicating with the vacuum responsive elements of a vacuum brake apparatus, a second chamber surrounding the first chamber, said chambers communicating at corresponding ends, and a valve seat interposed between the communicating ends of the chambers; a diaphragm covering both of said chambers and engageable with said valve seat to isolate one chamber from the other; a relief valve in said first chamber for opening the chamber to the atmosphere; means tending to hold saidrelief valve closed; a diaphragm lifting means adapted to occupy a neutral position free of said diaphragm and in engagement with said reliefvalve to hold the same open, and to occupy an operating position free of said relief valve and in engagement with said diaphragm to open communication between said chambers.

2. A control valve for vacuum brakes, comprising a housing structure having a chamber communicating with the vacuum responsive elements of a vacuum brake apparatus, a second chamber surrounding the first chamber, said chambers communicating at corresponding ends, and a valve seat interposed between the communicating ends of the chambers; a diaphragm covering both of said chambers and engageable with said valve seat to isolate one chamber from the other; a relief valve in said first chamber for opening the chamber to the atmosphere; means tending to hold said relief valve closed; a diaphragm lifting means adapted to occupy a neutral position free of said diaphragm and in engagement with said relief valve to hold the same open, and to occupy an operating position free of said relief valve and in engagement with said diaphragm to open communication between said chambers; an operating member for said lifting means; and a yieldable element interposed between the operating member and said lifting means to permit seating of the diaphragm in opposition to the urge of said lifting means.

3. In a control valve for vacuum brakes, a valve housing defining, a cylinder having ports at opposite ends, the first port being open to the atmosphere, a chamber communicating with the other port of said cylinder, said chamber being connected with a region of sub-atmospheric pressure, and a conduit intersecting said cylinder between said ports and communicating with vacuum responsive elements of a vacuum brake apparatus; a relief valve for said first port, means tending to close said relief valve; a flexible diaphragm positioned to control communication through the other port between said cylinder and said chamber; and operating means for opening either of the ports of said cylinder to connect said vacuum responsive elements with atmospheric pressure or with said region of sub-atmospheric pressure. l

4. In a control valve for vacuum brakes, a valve housing defining, a cylinder having ports at opposite ends, the first port being open to the atmosphere, a chamber communicating with the other port of said cylinder, said chamber being connected with a region of sub-atmospheric pressure, and a conduit intersecting said cylinder between said ports and communicating with vacuum responsive elements of a vacuum brake apparatus; a relief valve for said first port, means tending to close said relief valve; a flexible diaphragm positioned to control communication through the other port between said cylinder and said chamber; and operating means extending into said cylinder and movable in one direction to engage said diaphragm and open the port controlled thereby, and movable in the other direction to engage and open said relief valve; an actuator for said operating means; and a yieldable means interposed between said actuator and said operating means to permit closing of said diaphragm in opposition to the urge of said operating means.

5. In a control valve for vacuum brakes; a pair of complementary housing members; a diaphragm clamped therebetween; an annular valve seat in one of said housing members engageable with said diaphragm and defining an internal guide in the other housing member; a diaphragm lifting member slidably mounted in said guide and extending through the diaphragm into the internal port; an operating means for said lifting member; a .yieldable link between said opcrating means and lifting member responsive to movement of the diaphragm in opposition to the lifting member; a relief valve associated with the port communicating with the vacuum responsive element; means normally urging said relief valve closed; and a device connected with said lifting member for holding said relief valve open when said diaphragm is seated on said valve seat.

6. In a control valve for vacuum brakes, a yieldable diaphragm, one side exposed to atmospheric pressure; a housing member covering the other side of the diaphragm and defining a central port and an annular port separated by a diaphragm seat engageably by said diaphragm to isolate one port from the other, the annular port communicating with a region of sub-atmospheric pressure whereby a pressure differential is maintained on said diaphragm urging the same against said diaphragm seat, the central port communicating with a vacuum responsive element of a brake apparatus; a relief valve for exposing said vacuum responsive element to the atmosphere; means urging said relief valve to a closed position; and an operating means movable to engage and open either said diaphragm or said valve.

7. In a vehicle brake apparatus incorporating a brake actuating device responsive to sub-atmospheric pressure and adapted to be connected to r a region of sub-atmospheric pressure, of a control valve structure interposed between said device and said region comprising; a housing defining a chamber communicating with said device, a valve element for connecting said chamber with said region of sub-atmospheric pressure, a control for variably positioning said valve element; means operative in opposition to said control and responsive to pressures in said brake actuating device and said chamber for disconnecting said chamber from said region of sub-atmospheric pressure; and relief valve means for opening said chamber to atmospheric pressure, said relief valve being engageable by said control alternatively with said valve element.

8. In a vehicle brake apparatus incorporating a brake actuating means responsive to sub-atmospheric pressure and connected to a region of such sub-atmospheric pressure; a control valve interposed'between said means and said region having a valve element urged to a seated position in response to sub-atmospheric pressure in said region and said brake actuating means; manually operable, yieldable, operating means for opening said valve elements to connect said region with said brake actuating means; a relief valve communicating with said brake actuating means for exposing the same toatmospheric pressure; and 

